A capacitance sensor of a touch display device is generally located below a protective cover, where an electrode A and an electrode B are patterned in a certain way to form a two-dimensional matrix, each touch area (as illustrated in FIG. 1) of the matrix corresponds to a characteristic capacitance.
As the electrode A and the electrode B are located in the same layer, a gap between the two electrodes is designed to prevent a short circuit. Moreover, some suspension blocks P have to be inserted between the electrode A and the electrode B to improve visual effect. Due to the affect from manufacturing processes or dust in a factory, however, it is likely that an instable short circuit may occur between the electrodes A and B as well as the suspension blocks. For example, metal particles between the suspension block P and the electrode A will change its contacting status with the suspension block P and the electrode A when the touch control devices vibrates, such that variation values of the characteristic capacitance under different stages change dramatically, resulting in a touch event. But such touch event is actually not intended under these circumstances, that is, an undesired mis-determination happened.